Elimination of breathing artefacts from impedance cardiograms at rest and during exercise

  • O. Eiken
  • P. Segerhammar
Physiological Measurement


A signal processing technique was developed by which breathing artefacts can be eliminated from impedance cardiograms. The breathing component of the transthoracic impedance signal is identified by a moving-window technique using linear regression analysis, the window span being determined by the current R-R interval of the ECG. Satisfactory beat-by-beat stroke volume measurements were obtained when the method was applied to eliminate simulated breathing artefacts superimposed on distortion-free impedance signals from human subjects. In subjects performing moderate to heavy exercise the potential capability of the method to retrieve the cardiogenic impedance signal in the presence of severe interference caused by exercise hyperpnoea was demonstrated, permitting distortion-free beat-by-beat stroke volume estimations.


Breathing-artefact elimination Cardiac output Impedance cardiography Muscular exercise Stroke volume 


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Copyright information

© IFMBE 1988

Authors and Affiliations

  • O. Eiken
    • 1
  • P. Segerhammar
    • 1
  1. 1.Department of Environmental MedicineKarolinska InstitutetStockholmSweden

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